Projection lamp aiming device



April 22, 1958 R. N. FALGE ET AL 2,831,262

PROJECTION LAMP AIMING DEVICE April 22, 1958' R. N. FALGE ET AL2,831,262

PROJECTION LAMP AIMING DEVICE Arron/fr R. N. FALGE ET AL 2,831,262PROJECTION LAMP AIMING DEVICE Api-i122, 195s 3 Sheets-Sheet 5 Filedsept. 1, 1955 m if o www@ wir ,am WM @w www PROJECTION LAMP AIMINGDEVICE Robert N. Falge, Anderson, Ind., and Earl M. Brohl, Flint, Mich.,assignors to General Motors Corporation, Detroit, Mich., a corporationof Delaware Application September 1, 1955, Serial No. 532,079 6 Claims.(Cl. 33-180) This invention relates to aiming of projection lamps andmore particularly to an improved instrument for use in aiming the lightbeam projected from such lamps. The invention is especially adapted foruse in aiming vehicle headlamps of the type having an aiming surface ina predetermined angular relation with the projected light beamdirection. Lamps of this type are known, and are referred to herein, aspre-aimed lamps. A preaimed lamp, especially suitable for a vehicleheadlamp, is disclosed and claimed in U. S. application Serial No.515,684, tiled by Charles F. Arnold and Edward N. Cole on lune 15, 1955and assigned to the assignee of the present invention.

The proper aim of vehicle headlamps is, of course, of great importanceto the effective and safe operation of an automobile vehicle. Ho provideadequate roadway illumination it is necessary to employ lamps of highcandlepower with accurately controlled light distribution anddirectivty. In general, the desired result is to provide illumination ofthe roadway suliciently far in advance of the vehicle to permitadjustment of the vehicle operation in accordance with the roadwayconditions while controlling the light beam direction in such mannerthat the operator of an oncoming vehicle is not blinded.

In the aiming of vehicle headlamps, whether effected by means of opticalor geometrical instruments or a combination of both, it is a practice todirect the light beam from each of the headlamps at a predeterminedangle with respect to the straight-ahead direction or longitudinal axisof the vehicle. The headlamps may be aimed, for example, on the upperbeam with the most intense portion thereof directed straight ahead andslightly downward. This directivty of the light beam may be defined interms of angular deflection in the horizontal and vertical planes whenthe vehicle is in a level attitude such as that assumed when parked on alevel surface. In the ordinary, commercially produced vehicle headlampthere is a random angular deviation between the direction of the lightbeam projected from the lamp and the mounting rim or seating surface ofthe lamp. This angular deviation occurs because of inaccuracies infilament position or the relative location of other parts of the opticalsystem. Precision aiming of the vehicle lamps cannot be achieved withouttaking into account both of the aforementioned deflection and deviationangles. The prior art aiming instruments which can be employed to takethese factors into account may be characterized as being undulycomplicated, requiring a skilled operator, and not adapted for use withthe pre-aimed type of lamp.

It is an object of this invention to provide an improved aiminginstrument for lamps which is accurate in operation, simply and ruggedin construction and inexpensive to manufacture.

It is a further object of this invention to provide an aiming instrumentwhich requires a minimum of parts and adjustment, and may be used by anunskilled operator to obtain precise aiming of a projection lamp.

A further object is to provide a geometrical aiming nitecl tates ice .device which is elective to establish the directivty of the light beamprojected from the lamp with optical precision.

An additional object is to provide an aiming instrument for vehicleheadlamps which may be used for ascertaining the inclination of thevehicle during the aiming operation to establish a datum indication forthe indicatingk means on the aiming instrument.

ln the attainment of these and other objects, there is provided asupport member including a seating surface adapted to be attached to thelamp for movement therewith. An aiming element is provided on thesupportmember and inclu-des level indicating means for establishing aimin the vertical plane. Another aiming element is disposedon the supportmember and extends at a predetermined angle with respect to the seatingsurface for alignment with reference means to establish aim in thehorizontal plane. The support member is provided with elements adaptedto provide support for the instrument on an inclined surface to obtain adatum indication for the level indicating means.

A more complete understanding of the invention may be had from thedetailed'description which follows, taken with the accompanying drawingsin which:

Figure 1 is a plan view of the inventive aiming instrument.

Figure 2 illustrates the manner in which the aiming instrument is usedto obtain a datum indication.

Figure 3 is a side elevation view of the instrument attached to avehicle headlamp.

Figure 4 is a front view of a pair of the aiming instruments installedon the headlamps of a vehicle.

Figure 5 is a plan view of the installation shown in Figure 4.

The drawings represent an illustrative embodiment of the invention in anaiming instrument especially adapted for use in aiming vehicle headlampsof the pre-aimed type. Referring now to Figures 1 and `3, the aiminginstrument, designated generally at 10, comprises a support member 12 ofmetal construction and preferably of circular cup-shaped configuration.The support member 12 is provided with an annular seating surface14disposed adjacent the periphery which terminates in a llange portion16. To provide for attachment of the support member to the lamp for usethere is provided a plurality of securing means or plungers 18'extendingthrough circumferentially spaced bosses 20 disposed near the peripheryof the support member 12. The pluugers 18` terminate in hook portions 22adapted to engage mounting structure for the lamp, to be describedsubsequently. A coil spring 24, coaxial with each of the plungers 18, isinterposed between the boss 20 andan operating handle 26 of -the plunger18 to resiliently urge the hook 22 toward a retracted position.

The supportmember 12 is provided with a central boss i 28 upon which isrigidly mounted a first aiming element or arm 30. The arm 30 extendsoutwardly from the support member 12 yat a predetermined angle,preferably perpendicular, to the plane of the seating surface 14. Thearm 30 is suitably of metal construction of channelshaped configurationand may be provided with a reinforcing rib 32 to enhance the rigidity ofthe structure.

Mounted upon the arm 30 is a level indicating device v such as spiritlevel 34 provided with spaced mounting lugs 36 and 36'. The mountinglugs 36 and 36 are connected with the arm 30 by a pair of adjustingscrews 38 and 38 extending through coil springs 40 and 1&0',respectively.

This construction provides a resilient support for the spirit level 34and facilitates adjustment of the inclination thereof with respect tothe arm 30 and hence, seating surface 14.

kA second aiming element or cross bar 42 is rigidly confy `nectcd to thearm 3l) and extends transversely thereof at Patented Apr. 22, 1958` apredetermined angle, preferably parallel, to the seating surface lli.The cross bar 42 also may be of metal construction and is provided witha pair of forwardly extending protrusions and d4'. Adjacent theprotrusion 44' the cross bar i2 is provided with a suitable anchoringdevice or 'lug 46 to accommodate the connection of a exible cord 48.

The instrument lll is provided with a support element or foot 5t) whichdepends from the cross'bar 42 and a support element 32 which isconstituted by the lowermost portion of the flange lo. lt is noted thatthe support elements Sil and d2 terminate in a plane which is disposedin a known angular relationship, preferably perpendicular, to theseating surface 14. This arrangement of the support elements Sli and 52'aords stable support for the aiming instrument 1t? when disposed on aplane surface and the seating surface will assume a known dispositionwith respect to the plane surface. The advantages of'this constructionwill become apparent consequently.

As shown in Figures l and 3, the laiming instrument is adapted forattachment to a vehicle headlamp Sli.v The headlamp 54, in theillustration embodiment, is of the well known all glass sealed beamconstruction and is provided with pre-aiming structure set forth intheabove mentioned application. The lamp 54 comprises a re- Hector S6 and alens SS, integrally joined by fusion at a peripheral flange or rim 6l),enclosing a larnentary light source (not shown). The rim 6G is providedwith the usual seating surfaces 62, and orienting lugs 64. Disposedcircumlcrentially adjacent the periphery of the lens A 5S are `aplurality of aiming projections 66 which dene an aiming plane on thelamp having a known angular position with respect to the direction oftheV light beam projected from the lamp. The aiming plane defined by theprojections 66 is preferably inclined with respect to the direction ofthe light beam to incorporated the'desired horizontal and verticaldeflection or aiming angles. Thus in the preferred embodiment the aimingplane accounts for both the aforementioned deviation1 and deilectionangles.

The lamp 5d is dirigibly mounted in the vehicle body 68 which supports ahousing member 7l) terminating in an annular socket 72. A casing member74 is provided with a seating liange 1T having suitably orientedrecesses' for coaction with the orienting lugs 64 on the lamp, and isseated in the socket portion 72. A retainingring 78 is provided with aflange Sli engaging the rim 60 of the lamp 54. The retaining ring "/8 issecured to the casing 70 by interposed tension spring 82 and adjustingscrew 84. The adjusting screw may be advancedor retracted in a threadedlug to impart angular motion to the lamp S-i in the vertical plane.Similar adjusting structure (not shown) is provided for impartingangular motion to the lamp in the horizontal plane.

Before proceeding with the aiming operation, the operation of theinstrument for ascertaining the datum indication or the level indicatingdevice will be described. In aiming a headlamp of the pre-aimed type itis necessary to adjust the aiming plane thereof to a position in whichit is in a predetermined angular relation to the longitudinal axis orstraight-ahead direction of the vehicle. ln a pre-aimed lamp in whichthe aiming plane is inclined with respect to the direction of the lightbeam to incorporate the desired horizontal and vertical deliection oraim angles, it is merely necessary to adjust the angularlposition of thelamp so that the aiming plane is perpendicular to the vehicle axis.fiable on the vehicle structure, it is desirable to `lo'cfut'edhe axiswith reference to portions oi the vehicle structure and a horizontalplane. The headlamps of a conventional vehicle are disposedsymmetrically about the vehicle axis and corresponding points on the twoheadlamps or associated mounting structure lie on a line which isperpendicular to the axis of the vehicle. This line may serve as `aconvenient reference for obtainingv the desired aim Since this axis isnot readilyjidenti-A till .4 in the horizontal plane. With the vehicledisposed on a planev support surface the vehicle assumes an attitude inwhich its longitudinal axis is substantially parallel to the supportsurface. If the plane support surface is level or lies in a horizontalplane the vehicle 'axis also lies in a horizontal plane. Thus aiming inthe vertical plane may be accomplished by reference to a levelindicating means such as a spirit level or plumb bob. However, it isoften necessary or desirable to perform 'an aiming operation on vehicleheadlarnps with the vehicle supported on an inclined surface. ln manyservice stations, for example, space is not available to provide a levelsurface suitable for headlamp aiming. It is, of course, desirable to beable to perform the aiming operation on the driveway of gasolinestations and garages, to promote safe vehicle operation by widespreadadoption of headlamp aiming.

The manner in which the aiming instrument is adjusted to adapt it for anaiming operation with the vehicle on an inclined surface will beexplained with reference to the diagrammatic illustration of Figure 2.The surface or tloor 3S upon which the vehicle is to be parked is shownto be inclined at an exaggerated angle for explanatory purposes. Thevehicle front and rear wheels, represented by phantom lines 96 and 2 areto be located at the spaced points 94 and 96. At the points 94 and 96suitable blocks 9d and llll, respectively, are positioned to support abeam lo?. of suicient rigidity to support its own weight and that of theinstrument l) without deflection. The blocks 9S and 10d are of equalthickness and therefore the beam 102 assumes the slope or inclinationofa straight line connecting the spaced points. The aiming instrument 1l)is positioned on the beam 192 in the attitude shown and supported by thespacedv support elements Si) and 52. ln this position the seatingsurface 14 `is perpendicular to the surface of the ybeam 102. The levelindicating device' 34% is then adjusted by means of the adjusting screws38 and'SS to obtain a datum indication, preferably with the indicatorbubble of the spiritlevel centered. The level indicating means is thuspre-set for use of the aiming instrument on vehicles parked on theinclined surface 88. In performing the aiming operation, the aim of alamp in the vertical plane Will lbe established by adjusting the angularposition of the lamp until the indicating bubble of the spirit levelassumes the datum indication. In this condition, the seating'surface ldand the aiming plane of the lamp will be disposed in a planeperpendicular to the oor 88 and hence the straight-ahead direction ofthe vehicle.

The performance of the aiming operation will be described with referenceto Figures 4 and 5. The vehicle lll-4 is parked on the drive 8S, aspreviously described, and the aiming instrument lll is attached to oneof the vehicle headlamps and an identical aiming instrument l0isfattached to the other of the vehicle headlninps. This attachment, asshown in Figures 3 and 4, is accomplished by removing the headlamp trimpanel or door (not shown) from the body portion 68 surrounding thcheadlamp. T he retaining ring 78 is thereby exposed and the supportmember l2 is positioned over the lens of the lamp with the seatingsurface ld in close engagement with the aiming projections 66. in thisposition the plungcrs i8 are'advanced against the resistance of thc coilsprings 24 and manipulated to engage the hook 22 over the edge of theretaining ring.

To effect the aim in the horizontal plane the cord 4S is drawn tautbetween the anchor lugs do on the cross bars 42 of the two instrumentsi@ and l'.. The adjusting screws (not shown) of each lamp for rotatingthc lamp in the horizontal plane are advanced or retracted until thecord S is disposed tangent to the' protrusions t4 and 44' on each of theaiming devices and 36.

`When this condition is realized the aiming plane defined by aimingprojections is perpendicular in the horizontal plane to the longitudinalaxis or straight-ahead direction of the vehicle and the horizontalaiming is completed.

To eect the aim in the vertical plane for each lamp, the adjusting screw84 for rotation of the lamp in the vertical plane is advanced orretracted until the level indicating device 34 indicates the pre-setdatum value. In this condition the aiming plane of each lamp isperpendicular, in the vertical plane, to the longitudinal orstraight-ahead direction of the vehicle. This completes the aim in thevertical plane. The attainment of the desired positioning of the lampaiming planes by the aiming instrument ensures that the light beam isdirected with great accuracy. It will be appreciated that the desiredhorizontal and vertical aim angles may be incorporated in theinclination of the aiming plate, as described, or may be incorporated inthe structure of the aiming instrument. in either case the operation isthe same.

Although the invention has been described with respect to a particularembodiment, such description is not to be construed in a limiting sense.Many variations and modifications within the spirit and scope of theinvention will now occur to those skilled in the art. For a denition ofthe invention reference is made to the appended claims.

We claim:

l. An instrument for aiming the light beam of a vehicle headlamp of thetype having an aiming surface disposed in known relation to the lightbeam direction comprising a support member having a seating surfacethereon adapted to engage said aiming surface, means for securing thesupport member to a headlamp installed in a Vehicle, a first memberconnected to the support member and extending at a predetermined anglewith respect to said seating surface in one plane, a second memberrigidly connected to the rst member and extending transversely thereofat a predetermined angle with respect to said seating surface in atransverse plane, level indicating means, and an adjusting mechanismincluding resilient resisting means interconnecting the level indicatingmeans and the rst member for presetting the indicating means to a datumvalue.

2. An instrument for aiming a dirigible, vehicle mounted lamp in thehorizontal and vertical planes, comprising a support member including aseating portion, means for attaching the support member to the lamp withthe seating surface in fixed relation with the lamp for movementtherewith, a transversely extending part on the support member foralignment with reference means for aiming in the horizontal plane,plural spaced support parts on the support member disposed in a planehaving a predetermined angular relation to said seating portion, saidsupport parts being adapted to provide stable support for the supportmember upon a substantially plane, inclined surface, and levelindicating means adjustably mounted on the support member forestablishing aim in the vertical plane, said level indicating meansbeing presettable to a datum indication to compensate for inclination ofthe vehicle during aiming.

3. An aiming instrument for a dirigible, vehicle mounted lamp comprisinga support member having a seating surface adapted to engage an aimingsurface on the lamp, means for securing the support member to the lampfor movement therewith, a first aiming element extending outwardly fromthe support member in a direction perpendicular to the seating surfaceand including an adjustably mounted level indicating device, a secondaiming element extending in a direction parallel to the seating surfaceand supported adjacent the outermost end of the first aiming element,and means on one of said elements and on said support member to providestable support of the instrument with seating surface perpendicular to aplane supporting surface whereby the level indicating device may beadjusted to a datum indication.

4. In combination with a dirigibly mounted lamp of the type including anaiming surface having a predetermined angular relation to the directionof the light beam projected from the lamp, a retaining -member forsecuring the lamp in a dirigible mounting, a support member having aseating surface adapted to engage the aiming surface, means for securingthe support member to the retaining member for movement with the lamp, arst aiming element extending outwardly from the support member inpredetermined direction with respect to the seating surface, a levelindicating device adjustably mounted on the first aiming element forestablishing the desired aim in a vertical plane, and a second aimingelement extending transversely of and rigidly supported by the firstaiming element, said second aiming element extending in a predetermineddirection with respect to the seating surface for establishing thedesired aim in a horizontal plane.

5. In combination with a dirigibly mounted lamp of the type including anaiming surface in predetermined angular relation to the direction of thelight beam projected from the lamp, a support member having a seatingsurface thereon adapted to engage the aiming surface, means for securingthe support member to the lamp for movement therewith, a first aimingelement on the support member extending outwardly therefrom at fixedpredetermined angle with respect to the seating surface, a levelindicating device on said element for indicating the desired aim of thelight beam in a vertical plane, and a second aiming element mounted onand extending transversely of the tirst aiming element at a ixedpredetermined angle with respect to the seating surface for indicatingthe desired aim of the light beam in a horizontal plane.

6, An aiming instrument for a dirigible, vehicle mounted lamp of thetype including plural spaced aiming projections on the lens defining anaiming plane; said instrument comprising a support member including anannular seating surface, plural spring-urged plungers extending throughthe support member for securing the support member to the lamp with theseating surface in close engagement with the aiming projections, an armmounted on the support member and extending perpendicularly outwardlyfrom the seating surface, a spirit level adjustably mounted on the arm,a cross bar on said arm adjacent the outermost end and extendingtransversely thereof in a direction parallel to the seating surface, anda support portion on the support member and a support portion adjacentthe outermost end of the arm, said support portions terminating in aplane perpendicular to the seating surface and adapted to provide stablesupport for the instrument when disposed upon a plane surface.

References Cited in the tile of this patent UNITED STATES PATENTS1,987,692 Linendoll et al. Jan. l5, 1935 2,557,893 Russell et al. June19, 1951 2,609,611 Dickson Sept. 9, 1952 U S DEPARTMENT OF COMMERCEPATENT- OFFICE CERTIFICATE OF CORRECTION Patent No., 2,831,262 RobertN., Felge et al., April 22:7 195 It i's hereby certified that errorappears in the printed spec'ficato: of the above numbered patentrequiring correction and that the said Let ser: Patent should read ascorrected below.

Column l, line 30 for' "automobile" 'read' automotive m; same liney `forWH0 read To me; column 3, linev 19, for"oorrsequently" read subsequently--5 line 22, for ""illustration" read m illustrative line; 36, for"incorporated" read incorporate "we Signed and sealed this lOth day ofJune 1958,',

(SEAL) Attest:

KARL :in

AXLINE ROBERT C. WATSON Attesting Officer Comissioner of Patents

